Umbrella shaft having seven tubes



FIG. 1 is a perspective view of an umbrella shaft having seven tubes showing my new design;

FIG. 2 is a front plan view thereof;

FIG. 3 is a rear plan view thereof;

FIG. 4 is a left side plan view thereof;

FIG. 5 is a right side plan view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof; and,

FIG. 8 A to G shows the cross-sectional view of each tube of the umbrella shaft of my design. 

The ornamental design for an umbrella shaft having seven tubes, as shown and described. 